XIV. THE INDIAN BARNACLES OF THE SUBGENUS SC ALPELLUM. By N. Annandale, DSc, F.A.S.B., Superintendent of the Indian Musetim. In a former paper ^ I have discussed the subdivision of the genus Scalpellum and reviewed the indigenous species assigned to the subgenus Smilium. At present I propose to consider the remaining Indian species of the genus, that is to say those which fall into Hoek's^ divisions Arcoscalpelluni and Mesoscalpellum or into the subgenera recognized b}^ Pilsbry ^ under the names Arcoscalpel-luni and Scalpellum. It seems to me unnecessary to assign to these species more than subgeneric rank and I therefore include all under the common designation Scalpellum {s.s.) or subgenus Scal-pellum. To this subgenus I2 Indian species are here attributed, one of them not having as yet been described. This and three others are only known from the seas of British India ; four are known from the Malay Archipelago (one of them also from the western part of the Indian Ocean) and one from the Mid-Pacific ; one is found in the deeper parts of the western Pacific and the southern Atlantic as well as those of the Indian Ocean ; one is identical with a species described from the northern Atlantic off the American coast , and one has an extended distribution in both the Atlantic and the Indian Oceans. All are deep-sea forms only found, at any rate in tropical waters, at depths greater than one hundred fathoms. It is possible that the Scalpellum-isiunsi of the seas of British India will ultimately be proved capable of division into three geographical groups, of which one has a very restricted range, one is distributed in the deeper parts of the Indian and the western Pacific Oceans, while the third is scattered in the Indian and Atlantic Oceans at great or considerable depths. Most of the species are, however, as yet known from but few specimens and it is there-fore not surprising that the distribution often seems to be extra-ordinarily discontinuous. This fact also makes it impossible to be dogmatic as regards specific limits, for variation is great in some species that are well known. The following list gives the names of the species as yet recorded from the Bay of Bengal and the Arabian Sea, and also a general statement as to the known range of each : — 1 Rec. Ind. Mus. V, p. 145, 1910. 4 Siboga-Exped., Mon. XXXIrt, p. 58, 1907. 3 Proc. Acad. Nat. Sci. Philadelphia, p. 104, 1908.
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